ALL DIGITAL SEMI-BLIND OVERSAMPLING CLOCK DATA RECOVERY CIRCUITRY AND METHOD THEREIN

摘要

According to embodiments of the present invention, a semi-blind oversampling clock data recovery device includes a blind oversampling part and a digital phase fixing loop. The digital phase fixing loop includes a digital control oscillator and a digital filter part. In an approximate phase fixing step, an approximate oscillation signal is generated when an approximate oscillation signal generated in the digital control oscillator is synchronized with a reference clock. In a fine phase tracing step, the digital control oscillator provides oversampling clocks to the blind oversampling part. Based on FIFO usage information on the storage speed of data extracted from an FIFO register in the blind oversampling part, the digital control oscillator controls the phase and frequency of the oversampling clock according to a fine phase control signal generated by a digital filter part.